Medical lead adaptor having rotatable locking clip mechanism

ABSTRACT

A medical lead adaptor that provides a rapid, secure, insulated connection of the lead connector end assembly of a cardiac lead having electrodes adapted to be placed in or on the body with an external medical device. The adaptor connector assembly is configured with an elongated receptacle to accept a bipolar, in-line, or a unipolar lead connector end sharing common dimensions. The elongated receptacle includes connector pin and ring receptacle contacts spaced apart from one another. In a preferred embodiment, an elongated slot extends laterally with respect to the elongated receptacle and cooperates with a lock mechanism to permit lateral insertion of the lead connector end assembly. A stylet wire is then inserted into a cardiac lead body lumen, in the elongated receptacle. When inserted therein, the lead connector ring or pin is nested into contact with the ring or pin receptacle contacts and is held there by the lock mechanism.

CROSS-REFERENCE TO RELATED APPLICATIONS

Reference is hereby made to commonly assigned, U.S. patent applicationSer. No. 08/843,084, filed on even date herewith, now U.S. Pat. No.5,782,892, for MEDICAL LEAD ADAPTOR in the names of V. P. Castle et al.

FIELD OF THE INVENTION

The present invention generally relates a medical lead adaptor formaking a temporary connection between a medical lead and an externalmedical device, particularly for making the connection of a permanent ortemporary cardiac lead or heart wire with an external cardiac monitor orstimulator, depending on the nature of the implantable cardiac lead orheart wire.

BACKGROUND OF THE INVENTION

The earliest instances of relatively prolonged cardiac stimulation,namely cardiac pacing, of a patient's heart was effected throughimplanted cardiac leads attached to the heart muscle at distal electrodeends and extended through an incision in the patient's skin. Initially,cardiac pacing was employed during postoperative recovery from cardiacsurgery, and the attachment to the heart was made to the epicardiumduring the surgical procedure. To effect unipolar pacing of the heart, asingle such implantable pacing lead was employed in conjunction with asubcutaneously implanted or skin surface attached return electrodecoupled to an external lead conductor. To effect bipolar pacing of theheart, two such implantable pacing leads were implanted with theelectrode ends implanted a distance apart. Initially, the attachmentmechanism typically required a second surgical procedure to remove thedistal electrode(s) and the pacing lead(s).

The attachment of the proximal ends of the lead conductors to thetemporary cardiac pacemaker connector elements was initially effected bysimply stripping insulation from the proximal conductor ends, insertingthe bare conductor ends around or through transverse openings inthreaded posts, and tightening down thumb nuts. Later, finishedconnector pins were formed at the proximal connector ends of the leadbodies that could be inserted into end openings of the thumb nuts andconnector posts.

Implantable pacing leads evolved into permanent, unipolar and bipolar,endocardial and epicardial, pacing leads for chronic implantation in apatient and with proximal electrical connector assemblies connected withconnector elements of a totally implanted, cardiac pacemaker pulsegenerator. To withstand stress, implantable pacing lead conductors wereformed of coiled wire and inserted within an insulative lead body lumen,thereby providing a coiled wire lumen that was sized to receive astiffening stylet wire to assist transvenous implantation of endocardialpacing leads. The proximal end of the coiled wire conductor was attachedto a tubular connector pin at the terminus of the lead connector endshaped to be received in the connector assembly of the implantablepacemaker pulse generator. In the case of endocardial permanent pacingleads, the connector pin was formed with a lumen therein aligned withthe coiled wire lumen so that the stiffening stylet wire could beinserted down the length of the lead body, used during the transvenousintroduction, and withdrawn after placement of the distal electrode wasachieved. Many of these features are employed in current permanentpacing leads.

More recently, bipolar and multi-polar permanently implantable pacingleads and leads for use in pacing and cardioversion/defibrillation(collectively referred to as permanent implantable cardiac leads) havebeen developed using coaxially arranged, coiled wire conductors and/orparallel-wound, multi-filar coiled wire conductors. In the case ofendocardial cardiac leads, the stylet wire lumen is employed to receivethe stiffening stylet wire for implantation as described above. Theproximal connector end assemblies are formed with at least two spacedapart lead connector elements arranged in-line from a proximal leadconnector pin to at least one more distally located ring-shaped elementor lead connector ring. Typical bipolar in-line lead connectorassemblies for multi-filar, coiled wire conductors are shown, forexample, in commonly assigned U.S. Pat. Nos. 4,944,088 and 4,951,687 and5,007,435, respectively, incorporated herein by reference.

Different manufacturers have produced implantable cardiac leads withlead connector end assemblies that match the connector block terminalsof implantable medical devices of the same manufacturer. In recentyears, one dimensional pacemaker connector standard has been madeimplemented, namely the low profile connector "IS-1" standard (ISO5841-3:1992(E)) for bipolar in-line and unipolar lead connector endassemblies. Other permanent, bipolar, in-line, cardiac lead connectorend assemblies conform dimensionally with the MEDTRONIC 3.2 mm lowprofile connector standard. Certain permanent unipolar cardiac leadconnector end assemblies conform dimensionally with the MEDTRONIC 5 mmconnector standard.

Unipolar and bipolar, temporary endocardial pacing leads and temporaryepicardial heart wires were also developed for implantation of thedistal electrode(s) thereof in contact with the endocardium or suturedthrough the epicardium of the hearts of hospitalized patients. The leadbody size of these temporary pacing leads and heart wires has typicallybeen smaller than that of permanent cardiac leads because of the absenceof an internal wire coil lumen for receiving a stiffening stylet wire.Still, in the case of bipolar temporary pacing leads and heart wires,either a lead connector pin and ring set having comparable separationsapart to those of permanent cardiac leads or bifurcated lead connectorassemblies are employed providing a pair of lead connector pins.Exemplary temporary bipolar pacing leads include the MEDTRONIC® TEMPTRONtemporary pacing leads having a uniform diameter, in-line, connector pinand ring assembly. Exemplary heart wires include the MEDTRONIC® ModelNos. 6491, 6492, 6494 and 6500 unipolar heart wires and the Model 6495bipolar heart wire as described in commonly assigned U.S. Pat. No.4,341,226, incorporated herein by reference.

During a hospitalization, a heart wire or temporary pacing lead of thesetypes may be implanted to allow monitoring and demand pacing of theheart as the patient recovers from cardiac surgery or another condition.In addition, it may be necessary at times to connect the proximalconnector end of a permanent cardiac lead already implanted in a patientto a temporary external pacemaker. The proximal connector end assembliesin each case are attached, for example, to external medical deviceconnector elements of MEDTRONIC® Model Nos. 5348 or 5388 external singlechamber or dual chamber cardiac pacemakers. The external medical deviceconnector elements of such external cardiac pacemakers can constituteeither spaced RCA type female sockets or a shrouded connector housingthat are not compatible with cardiac lead connector end assemblies.

Therefore, when a bipolar heart wire or permanent or temporary pacinglead is to be connected, it is necessary to use a further "patientcable" adaptor to complete the connection. The MEDTRONIC® Model 5433A/Vor the Model 5832/S reusable safety cables are employed to make theconnection between the temporary pacemaker and the proximal connectorends of the heart wire or temporary pacing lead. Alternatively, theMEDTRONIC® Model 5455/S or the Model 5833/S disposable cable is employedto make the connection between the temporary pacemaker and the proximalconnector ends of a temporary pacing lead.

A similar situation arises during a surgical implantation of a pacemakeror pacemaker-cardioverter-defibrillator including a permanent cardiaclead or lead system or the replacement connection of a implantable pulsegenerator of one of these types with a pre-existing permanent cardiaclead or lead system. During or after implantation of the implantablecardiac lead(s), an external pacing system analyzer, e.g., theMEDTRONIC® Model No. 5311B PSA, is attached to the proximal leadconnector end assembly accessible through the incision to assess theperformance of the system. Again, the Model 5311B connector elements arenot compatible with the lead connector end elements for safety reasons.It is necessary to use either a disposable or a reusable "surgicalcable" adaptor to complete the connection. Examples include theMEDTRONIC® Model 5410/S reusable surgical cable and the combination ofthe MEDTRONIC® Model 5411/S reusable adaptor and Model 5455/S disposablesurgical cable.

Some of the above-identified patient and surgical cable adaptorsconstitute simply a connector assembly at one end that is compatiblewith the PSA or temporary pacemaker terminals, an external lead bodyenclosing the external lead conductors, and lead connector elementconnectors at the other end. Typically, two to four conductors areincluded in the lead body, and a set of two or four alligator clips areprovided at the other ends for attachment to the lead connector ring andpin of one or two implantable cardiac leads.

Other, typically reusable patient and surgical cables employ a mechanismfor receiving the proximal connector ends of the heart wire, temporarypacing lead or permanent cardiac lead. For example, either RCA typefemale sockets are used or a dual thumb screw attachment mechanism isused in the above-referenced MEDTRONIC® Model 5832/S and Model 5433A/Vreusable patient cables, respectively.

Commonly assigned U.S. Pat. Nos. 4,245,642 and 4,466,441 disclosemedical lead adaptors of the latter type wherein lead connector endassemblies are insertable into sockets of a housing to make electricalcontact with a single or two electrical contacts spaced apart therein toreceive bifurcated bipolar, in-line bipolar, or unipolar lead connectorrings and/or pins. The attachment is effected by tightening down thumbscrews to prevent the connector end assemblies from slipping out of thesocket openings of the housing in each case. It is not possible to makean attachment with a permanent pacing lead having a stylet wire fittedwithin the lead lumen and projecting out proximally through theconnector pin. This case can only be accommodated by the use ofalligator clips that attach across the connector rings and pins.

Such an attachment is not as secure and electrically isolated as wouldbe desirable. It is undesirable to either lose the connection or toallow an electrical static discharge or other shock or impulse to reachthe heart through the exposed lead connector ends. At present, it isnecessary to loop and tape the assembled adaptor lead and implantablelead body against the patient's body and also place tape over thealligator clips.

At times, it has been observed that the careless use of alligator clipscan damage the insulation sheathes adjacent to the lead connector endring or connector pin s. In IS-1 leads, damage to the insulating sheathand the seal rings on either side of the connector ring has beenobserved due to movement of the jaws of the alligator clips.

SUMMARY OF THE INVENTION

It is an object of the present invention to solve these problemsidentified with prior art methods and mechanisms for attaching anexternal medical device to an implantable cardiac lead of the typesincluding permanent cardiac leads, temporary pacing leads and heartwires of the types having unipolar lead connector end assemblies orbipolar, in-line, lead connector end assemblies.

The present invention is implemented in several embodiments of a medicallead adaptor having an adaptor connector assembly which provides a rapidand secure connection of the proximal connector end assembly of such animplantable cardiac lead an external medical device of the typesdescribed above. The secure attachment of the lead connector endassembly within a connector receptacle of the adaptor connector assemblyavoids inadvertent release during patient movement or manipulation ofthe implantable cardiac lead and the medical lead adaptor. Moreover, thelead connector element(s), i.e., the lead connector ring and/or pin, areelectrically isolated within or on the connector receptacle to minimizeaccidental contact with a conductive surface or medical personnel.

In each preferred embodiment wherein the connection is with apermanently implantable, endocardial cardiac lead, the medical leadadaptor is configured to allow the stiffening stylet wire to remainwithin the lead lumen and can be employed if necessary to re-positionthe distal end of the lead while the external medical device remainsattached. The secure attachment of the lead connector end assemblyavoids inadvertent release during manipulation of the cardiac lead bodyand stiffening stylet wire. Moreover, the lead connector element(s),i.e., the lead connector ring and/or pin are electrically isolatedwithin a connector receptacle to avoid contact while manipulating thestiffening stylet wire and cardiac lead body.

The medical lead adaptor of the present invention advantageouslyminimizes inadvertent release of contact with the lead conductor pin andring attendant to the prior art attachment mechanisms that allowed theuse of the stylet wire.

The medical lead adaptor of the present invention also is easily openedand closed without the need to tighten down threaded thumb screws or thelike.

The medical lead adaptor of the present invention also advantageouslyminimizes the possibility of damage to the insulating sleeves of bipolarin-line cardiac lead connector assemblies by ensuring that they can onlybe inserted in alignment with receptacle contacts within the elongatedreceptacle.

Moreover, the preferred embodiments of the present invention can bereadily re-sterilized using autoclave or ethylene oxide sterilization orother sterilization methods because of their relatively openconfigurations, allowing re-use of the medical lead adaptors andconsiderable savings to the medical facility.

In the preferred embodiments, the elongated receptacle in the adaptorconnector assembly is shaped to receive the lead connector end assemblyin a nesting manner so that it cannot axially move therein. A lockingmechanism is provided for locking the lead connector end assembly in theelongated receptacle so that the lead connector elements are in contactwith the receptacle contacts in a locked position. The lead connectorend assembly is laterally inserted or withdrawn through an elongatedslot when the locking mechanism is manipulated to an open position. If astiffening stylet is present in the implantable cardiac lead, the styletwire projecting proximally from the lead connector end assembly islaterally inserted or withdrawn with the lead connector end assembly. Avariety of adaptor connector assemblies are disclosed in preferredembodiments of the invention illustrating exemplary configurations ofelongated receptacles, receptacle contacts, and locking mechanisms forperforming these functions.

In the first preferred embodiment, the implantable lead body and theexternal lead body extend in opposite directions away from opposite endsof the adaptor connector assembly. A locking clip closes the laterallyextending slot in a housing through which the lead connector assemblyand the stylet wire are inserted into the elongated receptacle.Therefore, the lead connector end assembly is securely attached withinthe elongated receptacle of the adaptor connector assembly even if oneor the other of the opposed lead bodies are accidentally pulled on.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects, advantages and features of the presentinvention will be appreciated as the same becomes better understood byreference to the following detailed description of the preferredembodiment of the invention when considered in connection with theaccompanying drawings, in which like numbered reference numbersdesignate like parts throughout the figures thereof, and wherein:

FIG. 1 is a simplified schematic view of an implanted permanent cardiaclead of the types described above implanted in a patient and coupled tothe adaptor connector assembly of the medical adaptor of the firstpreferred embodiment of the present invention;

FIG. 2 is an exploded isometric partial view of the proximal end of apermanent cardiac lead oriented to be inserted into the connectorreceptacle of the adaptor connector assembly of the medical lead adaptorof the first preferred embodiment of the present invention;

FIG. 3 is an isometric partial view of the proximal end of a permanentcardiac lead inserted into the connector receptacle of the adaptorconnector assembly of the first preferred embodiment of the presentinvention;

FIG. 4 is an isometric partial view of the adaptor connector assembly ofthe first preferred embodiment of the present invention;

FIGS. 5-7 are top, side and end partial views of the adaptor connectorassembly of FIG. 3;

FIGS. 8 and 9 are first and second isometric side views of a secondpreferred embodiment of a medical lead adaptor in accordance with theinvention;

FIGS. 10-13 are plan, side, and opposite end views of the secondpreferred embodiment of the medical lead adaptor depicted in FIGS. 8 and9;

FIGS. 14 and 15 are first and second isometric side views of a thirdpreferred embodiment of a medical lead adaptor connector assembly inaccordance with the invention;

FIGS. 16-18 are top, side, and end views of the third preferredembodiment of the medical lead adaptor connector assembly depicted inFIGS. 14 and 15;

FIG. 19 is an isometric side view of a fourth preferred embodiment of amedical lead adaptor connector assembly in accordance with theinvention;

FIGS. 20 and 21 are top and side views of the fourth preferredembodiment of the medical lead adaptor connector assembly depicted inFIG. 19;

FIG. 22 is an isometric side view of a fifth preferred embodiment of amedical lead adaptor connector assembly in accordance with theinvention;

FIGS. 23-25 are side and end views of the fifth preferred embodiment ofthe medical lead adaptor connector assembly depicted in FIG. 22 in theclosed position of the lock mechanism; and

FIG. 26 is an end view of the fifth preferred embodiment of the medicallead adaptor connector assembly depicted in FIG. 22 in the open positionof the lock mechanism.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is implemented in a number of embodiments ofmedical lead adaptor connector assemblies that each provide a rapid andsecure connection of the proximal lead connector end assembly of acardiac lead of the types described above with an external medicaldevice of one of the types described above. In each medical lead adaptorembodiment, an adaptor connector assembly is coupled to an external leadbody having one or preferably two external electrical conductors thereineach extending between a first external lead conductor end to a secondexternal lead conductor end at the second end of the external lead body.Each first external lead conductor end is electrically connected with anelectrical contact within the connector receptacle adapted to receiveand make electrical contact with a cardiac lead connector element. Eachsecond lead conductor end is coupled with an external lead connectorelement of an external lead connector assembly for making electricalcontact with the connector element of the external medical device. It iscontemplated that a variety of such medical lead adaptors with differingexternal lead connector end assemblies adapted to fit the connectorelements of differing external medical devices may be necessary.

In each medical lead adaptor embodiment of the present invention, theadaptor connector assembly is configured to accept a permanent cardiaclead connector end assembly with a stiffening stylet wire extendingproximally thereof. It is also contemplated that the adaptor connectorassembly may alternatively receive the lead connector ends of otherpermanent cardiac leads not employing a stiffening stylet wire. Inaddition, it is contemplated that temporary pacing leads and heart wiresthat share compatible lead connector element dimensions, that is,compatible spacing between and diameters of ring connector and/or pinconnector elements may also be received in the adaptor connectorassembly.

However, the lead connector end assemblies of permanent pacing leads,particularly, older lead models already implanted in patients, are notconsistent in dimensions, e.g. the spacing between and diameters of thering and pin connector elements of bipolar, in-line pacing leads. Ittherefore may be necessary to provide a variety of medical lead adaptorsin accordance with the present invention with compatibly dimensionedconnector receptacles and spaced apart receptacle contacts for differentlead types. Similarly, it may be necessary to provide a variety ofmedical lead adaptors with compatibly dimensioned connector receptaclesand receptacle contacts to accommodate the pin and/or ring leadconnector elements of various types of heart wires and temporary pacingleads.

The first preferred embodiment of the medical lead adaptor 10 for makinga rapid electrical connection between an external medical deviceconnector assembly (not shown) and a proximal lead connector endassembly 12 of an implantable cardiac lead 14 is shown in FIGS. 1-7. Themedical device connector assembly may take any of the forms used withthe above-referenced MEDTRONIC® Model 5311B PSA or Model 5348 and 5388temporary pacemakers. The proximal portion of the implantable cardiaclead 14 is shown in part and includes an elongated implantable lead body16 extending from the lead connector end assembly 12 toward the distalcardiac lead end (not shown). The distal cardiac lead end includes atleast one electrode implanted in contact with a heart chamber of thepatient 20, and may take any of the known forms for implantable cardiacleads of the type described above. The implantable lead body 16 containsan implantable lead conductor coupled between a distal electrode and aproximal lead connector element of the lead connector end assembly 12.

For purposes of illustration convenience, the implantable cardiac lead14 is depicted as a bipolar, in-line, permanent cardiac pacing leademploying co-axially wound, coiled wire, implantable lead conductors 22and 24 separated apart by an insulating sheath 26 and included within anouter insulating sheath 28. The outer implantable lead conductor 24 iscoupled to a respective lead connector ring 44, and the innerimplantable lead conductor 22 is coupled to a respective lead connectorpin 42. These connections may be effected in the manner shown, forexample, in the above-incorporated 5,007,435 patent. A lumen is formedwithin the inner implantable lead conductor 22 for receiving astiffening stylet wire 32 through a lumen end opening 38 in the leadconnector pin 42. When the stylet wire 32 is received in the lumen, itextends proximally from the lumen end opening 38 so that the stylet knob34 may be manipulated to rotate or axially extend or withdraw the styletwire 32 with respect to the lead body lumen.

The medical lead adaptor 10 includes an external lead body 50 having atleast one external electrical conductor therein extending between firstand second external lead conductor ends thereof. Preferably, theexternal lead body 50 encases two electrically isolated externalelectrical conductors 52 and 54 of any known configuration which arecoupled at their ends with two external lead connector elements of anexternal lead connector assembly 48. The external lead connectorassembly 48 may be of any of the types described above for makingelectrical contact with the external medical device terminals, e.g., thebifurcated connector pins 56 and 58 shown in FIG. 1 or a shroudedconnector assembly.

An adaptor connector assembly 60 for receiving the lead connector endassembly 12 is formed at the other end of the external lead body 50 andincludes a housing 62 and a rotatable lock mechanism or clip 64. Thehousing 62 is generally tubular having a generally cylindrical outersurface extending between proximal and distal housing ends 76, 78thereof. The housing 62 includes the elongated receptacle 70 (best shownin FIGS. 4 and 5) that extends from the proximal and distal housing ends76 and 78 and is shaped to conformably receive the lead connector endassembly 12 when laterally inserted therein through a receptacle slot80. At least the lead connector ring 44 and pin 42 of the lead connectorend assembly 12 are received in the elongated receptacle 70 between theproximal and distal housing ends 76, 78 so that they are not exposed.

The elongated receptacle 70 includes first or proximal and second ordistal receptacle contacts 72 and 74 positioned along the base andextending up the opposed sides of the elongated receptacle 70 for makingelectrical contact with lead connector pin 42 and ring 44, respectively.Each receptacle contact 72, 74 is formed of thin spring metal formed ina U-shape and is attached at the base thereof to one of the firstexternal lead conductor ends extending through the strain relief 66 andwithin the housing 62. In each case, the base is also attached to thebase of the elongated receptacle 70 and spaced apart to match thedistance between the lead connector pin 42 and ring 44. The openingwidths of the receptacle contacts 72 and 74 are sized to accommodate andbe slightly expanded by the diameters of the respective lead connectorend pin 42 and ring 44.

The receptacle slot 80 extends laterally of the elongated receptacle 70to the exterior housing surface for receiving the lead connector endassembly having the stylet wire 32 extending proximally from the lumenend opening 38. The receptacle slot 80 is narrowed adjacent to theproximal housing end 76 so that only the stylet wire 32 may be passedthrough it. The lead connector end assembly 12 and stylet wire 32 areshown in FIG. 2 poised to be inserted into the elongated receptacle 70laterally through receptacle slot 80. The lead connector end assembly 12is shown disposed in the elongated receptacle 70 with the proximallyextending stylet wire extending through the proximal end opening of theproximal housing end 76 in FIG. 3.

The rotatable locking clip 64 must be in the open position depicted inFIGS. 2 and 4-7 in order to insert or withdraw the lead connectorassembly 12 from the elongated receptacle 70. In this open position, anelongated clip slot 90 defined by the parallel opposed ends of therotatable locking clip 64, is aligned with the receptacle slot 80 toprovide lateral access through the aligned clip slot 90 and receptacleslot 80. The proximal lead connector end assembly 12 and stylet wire 32are retained in the elongated receptacle 70 by the rotation of therotatable locking clip 64 with respect to the housing 62 from the openposition to the closed or locked position depicted in FIGS. 1 and 3. Inthe closed and locked positions, the clip slot 90 is no longer alignedwith the receptacle slot 80 and elongated receptacle 70.

An exterior surface circumferential track 86 is formed around thecircumference of the tubular housing 62 in order to retain and guidemovement of the rotatable locking clip 64. The outer surfacecircumferential track 86 is defined by first and second spaced apartrails 82 and 84 extending around the circumference of the housing 62having rail diameters exceeding the track surface diameter therebetween.The locking clip 64 is generally C-shaped and cylindrical and has aninternal tracking surface that conforms with the outer surfacecircumferential track in width and diameter and is rotatable about thetubular housing 62 between the locked and open positions. In thismanner, the lock mechanism has an inner diameter that is sized withrespect to the rail diameters and the track surface diameter to berestrained by the spaced apart rails 82, 84 and to allow relativerotation of the locking clip 64 about the outer surface circumferentialtrack 86.

In use, the locking clip 64 is grasped and rotated while the tubularhousing 62 is grasped on opposite sides near the distal end 78 to holdit stationary. Through this rotation, the elongated clip slot 90 isalignable with the receptacle slot 80 on rotation of the lock mechanism64 to the open position. In the open position, the implantable leadconnector end assembly 12 and stylet wire 32 extending proximallytherefrom are inserted or withdrawn laterally through the aligned clipslot 90 and receptacle slot 80 into or from the elongated receptacle 70.In the closed position, the locking clip 64 locks the implantable leadconnector end assembly 12 in the elongated receptacle 70 assuring secureelectrical contact between a receptacle contact 72, 74 and acorresponding lead connector pin 42 and ring 44. The stylet wire 32 maybe withdrawn, inserted or manipulated because the locking clip 64 in thelocked position assures that the manipulation will not disturb theelectrical contact or expose the lead connector end ring and pins.

The first preferred embodiment may also be used without the presence ofthe stylet wire 32 or may be used with epicardial cardiac leads,temporary pacing leads or heart wires that do not have a lumen forreceiving a stiffening stylet 30.

The remaining FIGS. 8-26 depict further embodiments of the adaptorconnector assembly of the medical lead adaptor of the present inventionwherein at least certain features of the first embodiment areincorporated therein. In each illustrated embodiment, the externalmedical lead adaptor connector assembly 160, 260, 360 and 460 providesfor a rapid electrical connection between a medical device connectorassembly and a proximal lead connector end assembly 12 of an implantablecardiac lead 14. The implantable cardiac lead takes the form of lead 14described above with respect to the first embodiment depicted in FIG. 2and is of the type having an elongated implantable lead body 16extending from the lead connector end assembly toward the distal cardiaclead end. In particular, the implantable lead body 16 contains first andsecond spaced apart implantable lead conductors coupled to proximal anddistal lead connector end ring 44 and pin 42 as described above. Theimplantable lead body 16 has a lumen formed therein for receiving astylet wire 32 through a lumen end opening 38 in the connector end pin42. The stylet wire, when received in the lumen, extends proximally fromthe lumen end opening 38 so that the stylet wire 32 may be turned ormoved in and out to manipulate the distal end of the implantable medicallead in a manner well known in the art. Each of the embodiments depictedin FIGS. 8-26 are adapted to receive such a bipolar, in-line implantablelead connector end assembly 12 in an elongated receptacle 170, 270, 370,470 with the stylet wire 32 in the lead lumen and extending proximallyto be manipulated in this manner. Again, a unipolar implantable leadconnector end assembly sharing the same dimensions may be received inthe elongated receptacle and make an electrical connection with theproximal receptacle contact 172, 272, 372 or 472. And the elongatedreceptacles 170, 270, 370, 470 may receive such lead connector endassemblies without a stylet 30 in place. The stylet 30 may also bewithdrawn entirely or inserted into the lead lumen while the leadconnector end assembly 12 is received in the elongated receptacle 170,270, 370, 470

FIGS. 8-13 illustrate the second preferred embodiment of a medical leadadaptor 110 in accordance with the invention wherein the lock mechanismis effected by the spring material and form of the proximal and distalreceptacle contacts 172 and 174. The external lead body 150 has at leastfirst and second external electrical conductors therein each extendingbetween a first external lead conductor end thereof to a second externallead conductor end. The external lead body 150 is formed with anexternal lead connector assembly 148 that is particularly configured formaking electrical contact indirectly with an external medical deviceconnector assembly (not shown) through a further medical lead adaptor orcable. The external lead terminals 156 and 158 of the external leadconnector assembly 148 are electrically connected to the second ends ofthe external lead conductors within the external lead body 150. Theexternal lead terminals 156 and 158 have electrically exposed flatsurfaces bordered by insulating ridges for placement between the jaws ofalligator clips of a further medical lead adaptor or cable. Thisparticular external lead connector assembly 148 may be employed in anyof the embodiments of he invention.

An adaptor connector assembly 160 is coupled to the external lead body150 for receiving the lead connector end assembly (not shown) and formaking electrical contact between the first and second implantable leadconductors and first ends of the first and second external electricalconductors, respectively. The adaptor connector assembly 160 furtherincludes a generally rectangular housing 162 having parallel side andproximal and distal end walls defining an elongated receptacle 170. Theelongated receptacle 170 is shaped to conformably receive the leadconnector pin 42 and ring 44 of the lead connector end assembly 12 wheninserted therein through a side wall opening defining a receptacle slot180. The elongated receptacle 170 includes the first, or proximal, andsecond, or distal, receptacle contacts 172 and 174 positioned along saidelongated receptacle 170 for making electrical contact with the leadconnector pin 42 and ring 44, respectively.

A proximal end opening 176 formed in the proximal end of the housing 162receives the stylet wire extending proximally from the lead lumen endopening when the implantable cardiac lead connector end assembly 12 andstylet wire 32 are laterally inserted through the receptacle slot 180into the receptacle 170. A distal end opening 178 formed in the distalend of the housing 162 receives the lead body 16 extending distally fromthe lead connector end assembly 12 when the lead connector end assembly12 is laterally inserted through the receptacle slot 180 into thereceptacle 170.

The first, or proximal, and second, or distal, receptacle contacts 172and 174 are each formed of a conductor wire spring material formed in agenerally U-shape and are spaced apart within the elongated receptacle170 as depicted in FIGS. 8, 9 and 13. Each receptacle contact 172 and174 has a base section extending to first and second opposed branchsections that are positioned across from one another that terminate infree ends that are spaced apart to each define slot widths when relaxed.The free ends are also flared apart from the terminal slots as shown inthe figures. The terminal slot widths are less than the widths of therespective receptacle connector pin an ring and do not allow therespective lead connector elements to pass therethrough. However, theterminal slots of receptacle contacts 172 and 174 may be widened toallow the respective connector pin 42 and ring 44 to pass therethroughas they are pressed against the flared apart free ends. The opposedbranch and base sections are dimensioned to tightly engage the leadconnector pin 42 and ring 44 when they are received in the elongatedreceptacle 170 in the locked position and thereby provide the lockmechanism.

FIGS. 14-18 depict a third preferred embodiment of a medical leadadaptor connector assembly 260 in accordance with the invention. Forconvenience of illustration, neither the external lead connectorassembly coupled to an end of the external lead body 250 nor theexternal electrical conductors therein for making the electricalconnection with the external medical device are shown in FIGS. 14-18.

The adaptor connector assembly 260 is coupled to the external lead body250 through a strain relief 266. The adaptor connector assembly 260receives the lead connector end assembly 12 (not shown) for makingelectrical contact between the first and second implantable leadconductors and first ends of the first and second external electricalconductors, respectively. The adaptor connector assembly 260 furtherincludes generally arcuate and elongated housing halves 262 and 262'formed of insulating material each defining opposed portions of anelongated receptacle 270. The housing halves 262 and 262' extend betweenproximal and distal ends to define proximal and distal end openings 276and 278 of the elongated receptacle 270. The housing halves 262 and 262'are formed along the ends of first and second lever arms 292 and 294,respectively. The elongated receptacle 270 is further defined by theproximal and distal receptacle contacts 272 and 274 which are arcuatelyshaped to conformably receive the lead connector pin 42 and ring 44 ofthe lead connector end assembly 12 when inserted therein.

The elongated receptacle 270 includes the first or proximal and secondor distal receptacle contacts 272 and 274 positioned along saidelongated receptacle 270 for making electrical contact with theconnector pin 42 and ring 44, respectively. The proximal and distalreceptacle contacts 272 and 274 are each formed of a flat, thin,conductive spring material formed in a generally arcuate shape in theelongated receptacle 270 as depicted in FIGS. 15 and 18. The elongatedreceptacle 270 is otherwise relatively open at both ends and along theinterior side thereof between the housing halves 262 and 262'. The flat,thin, conductive spring material of each of the receptacle contacts 272,274 is bent and extends for lengths away from the elongated receptacle270 enclosed within the relatively flat, first and second lever arms 292and 294. Thus, the proximal and distal receptacle contacts 272 and 274effectively connect the first and second lever arms together and, withthe housing halves 262 and 262', define the elongated receptacle 270.The receptacle contacts 272 and 274 are electrically connected to firstand second external lead conductors in external lead body 250 throughconnections made within the lever arm 292.

The first and second receptacle contacts 272 and 274 are dimensioned totightly engage the connector pin 42 and ring 44, respectively, whenpositioned in the elongated receptacle 270 in the locked position. Thespring strength of the flexible elongated housing 262 and the U-shapedproximal or first and distal or second receptacle contacts 272 and 274provide the lock mechanism through pressure applied radially about thelead connector end assembly 12 fit tightly within the elongatedreceptacle 270.

The proximal end opening 276 receives the stylet wire 32 extendingproximally from the lead lumen end opening 38 when the implantablecardiac lead connector end assembly 12 and stylet wire 32 are laterallyinserted through the slot 280 into the receptacle 270. The distal endopening 278 receives the lead body 16 extending distally from the leadconnector end assembly 12 when it is laterally inserted through the slot280 into the receptacle 270.

The elongated lateral slot 280 extends along the space separating thehousing halves 262 and 262' having a slot width that does not allow thelead connector end assembly 12 to be passed through it in the closed andlocked positions. In this way, the lead connector assembly 12 is lockedinto the elongated receptacle 270 and cannot slip laterally out of theslot 280 after it is inserted through it. In order to allow the leadconnector assembly 12 to be laterally passed through the lateral slot280, a mechanism for increasing the slot width is provided. This unlockfeature of the lock mechanism comprises the first and second lever arms292 and 294 attached at fixed arm ends to the elongated housing halves262 and 262' along opposite edges of the lateral slot 280 and extendinglaterally away from it. The free ends are separated by a closed orlocked position distance, whereby force applied to the free ends thereofin the direction of the arrows F shown in FIG. 17 is transmitted to thefixed arm ends causing the width of the lateral slot 280 to be increasedto the open position. After the force F is released, the opening widthof slot 280 decreases to the closed position depicted in FIGS. 14-18 ora locked position embracing a lead connector end assembly 12 in theelongated receptacle 270.

FIGS. 19-21 depict a fourth preferred embodiment of a medical leadadaptor connector assembly 360 in accordance with the invention. Inthese figures, the external lead connector assembly coupled to an end ofthe external lead body 350 and the external electrical conductorstherein for making the electrical connection with the external medicaldevice are again not shown for convenience. This embodiment is avariation on the third embodiment, wherein the lock mechanism iseffected by spring loaded force beams 382 and 384 acting against theconnector pin 42 and ring 44 when the lead connector end assembly 12 isfitted in the receptacle 370.

An adaptor connector assembly 360 is coupled to the external lead body350 through a strain relief 366. The adaptor connector assembly 360receives the lead connector end assembly 12 (not shown) for makingelectrical contact between the first and second implantable leadconductors and first ends of the first and second external electricalconductors, respectively. The adaptor connector assembly 360 furtherincludes a generally flat housing 362 of insulating material providingan elongated receptacle 370 and first or proximal and second or distalreceptacle contacts 372 and 374. The elongated receptacle 370 alsoincludes the upstanding proximal receptacle end 356 shaped with a styletwire receiving proximal end opening 376. The elongated receptacle 370 isrelatively open and shaped to conformably receive the lead connector pin42 and ring 44 of the lead connector end assembly 12 when insertedtherein through a laterally extending slot 380 opened when the lockmechanism is displaced to the open position. The receptacle 370 includesthe first, or proximal, and second, or distal, receptacle contacts 372and 374 positioned along said elongated receptacle 370 for makingelectrical contact with the lead connector pin 42 and ring 44,respectively.

The proximal end opening 376 formed in the proximal end tab 356 receivesthe stylet wire 32 extending proximally from the lead lumen end opening38 when the implantable cardiac lead connector end assembly 12 andstylet wire 32 are laterally inserted into the receptacle 370. A distalend opening 378 formed in the distal end of the housing 362 receives thelead body 16 extending distally from the lead connector end assembly 12when it is laterally inserted into the receptacle 370 when the lockmechanism is displaced to provide the lateral slot 380.

The proximal and distal receptacle contacts 372 and 374 are each formedof saddle shaped conductive material formed to have generally arcuateshaped contact surfaces and are spaced apart within the elongatedreceptacle 370 as depicted in FIGS. 19 and 20. The receptacle contacts372 and 374 are electrically connected to first and second external leadconductors in external lead body 350. The arcuate, exposed, contactsurface of the receptacle contacts 372 and 374 generally conforms indiameter with the cylindrical surface diameter of the respectiveconnector pin 42 and ring 44, respectively. The arcuate, exposed,contact surface of the receptacle contacts 372 and 374 effectivelydefine the elongated receptacle 370.

In order to allow the lead connector assembly 12 to be laterally passedthrough the receptacle slot 380 and into the elongated receptacle 370, alock mechanism for increasing the slot width is provided. This lockmechanism comprises first and second lever arms 392 and 394 attachedtogether at fixed arm ends along leaf springs 386 and 388. The housing362 and the above-described components are formed at one fixed end ofthe lever arm 392. The lever arm 394 is coupled to one end of the forcebeams 382 and 384, the other ends of which are spaced from the arcuatesurfaces of the receptacle contacts 372 and 374, respectively. Thespacing is established by the leaf springs 386 and 388. Force applied inthe directions of arrows F to the free ends of the lever arms 392 and394 compresses the ends of the leaf springs 386 and 388 and separatesthe force beams 382 and 384 from the proximal and distal receptaclecontacts 372 and 374 causing the width of the slot 380 to be increasedto the open position. In the open position, the lead connector endassembly 12 and the stylet wire 32 can be laterally inserted orwithdrawn through the receptacle slot 380. After the force is released,the receptacle slot 380 width decreases to the closed position shown inFIGS. 19-21 or a locked position with the lead connector end assemblylocked into the elongated receptacle 370.

FIGS. 22-26 depict a fifth preferred embodiment of a medical leadadaptor connector assembly 460 in accordance with the invention. Forconvenience of illustration, the external lead connector assemblycoupled to an end of the external lead body 450 and the externalelectrical conductors therein for making the electrical connection withthe external medical device are not shown in FIGS. 22-26. In thisembodiment, the elongated receptacle 470 of the lead adaptor connectorassembly 450 shown within broken lines in FIG. 23 is aligned axially andoffset in parallel relation with the axis of the external lead body 450approximating the axial alignment of the first embodiment. As in thefirst embodiment, force applied on one is transmitted axially to theother of the implantable lead body (not shown) or the external lead body450. The formation and operation of the elongated receptacle 470 and thelock mechanism is somewhat inversely related to those of the third andfourth embodiments. In this embodiment, the lock mechanism is effectedby proximal and distal spring loaded force hooks 482 and 484,respectively, that bear against the connector pin 42 and ring 44 nestedin the proximal and distal receptacle contacts 472 and 474,respectively. The spring loading is effected by a torsion spring aroundand within the generally tubular body 462.

The adaptor connector assembly 460 is coupled to the external lead body450 through a strain relief 466 and tubular body 462. Generally planarwings or tabs 492 and 494 extend from the tubular body 462 throughplanar spring ends 486 and 488, respectively. The surface of tab 492forms a generally flat housing of electrically insulating materialdefining the bounds of the elongated receptacle 470 extending across theflat housing surface from a proximal edge 452 to a distal edge 454thereof. The elongated receptacle 470 includes the first or proximal andsecond or distal receptacle contacts 472 and 474 mounted to the surfaceof tab 492 and spaced apart to comply with the spacing of the leadconnector pin 44 and ring 42. The elongated receptacle 470 also includesthe proximal receptacle end 456 extending upward from the proximal edge452 and shaped with a stylet wire receiving proximal end opening 476.The elongated receptacle 470 is relatively open, and shaped toconformably receive the lead connector pin 42 and ring 44 of the leadconnector end assembly 12 when inserted therein through a lateralreceptacle slot 480 when the lock mechanism is displaced to the openposition as shown in FIG. 26.

The first and second receptacle contacts 472 and 474 are each formed ofconductive material formed to have contact surfaces and are spaced apartwithin the elongated receptacle 370 as depicted in FIGS. 22-24. Thefirst and second receptacle contacts 472 and 474 are each dimensionedand shaped to engage the connector pin 42 and ring 44 to prevent themfrom moving laterally when positioned in the elongated receptacle 470 inthe locked position. The first and second receptacle contacts 472 and474 are electrically connected through insulated conductors within tab492 to first and second external lead conductors of external lead body450 within the generally tubular body 462.

The proximal end opening 476 formed in the upstanding proximalreceptacle end 456 shaped with a stylet wire receiving proximal endopening 476 that receives the stylet wire 32 extending proximally fromthe lead lumen end opening 38 when the implantable cardiac leadconnector end assembly 12 and stylet wire 32 are laterally inserted intothe receptacle 470. The distal end of the elongated receptacle 470 atdistal side 454 is open and allows the lead body 16 to extend distallyfrom the lead connector end assembly 12 when it is laterally insertedinto the elongated receptacle 470 through the lateral receptacle slot480.

In order to allow the lead connector assembly 12 to be laterally passedthrough the lateral receptacle slot 480 and into the elongatedreceptacle 470, the lock mechanism is displaced from the closed positionof FIG. 25 to the open position of FIG. 27. The lock mechanism furthercomprises the first and second force hooks 482 and 484 which apply forceagainst the respective proximal connector pin 42 and ring 44 when theyare seated against the respective first and second receptacle contacts472 and 474. The first and second force hooks 482 and 484 have curvedfree ends and fixed ends that are attached to the interior surface ofthe tab 494.

The curved free ends of the first and second force hooks 482 and 484 areextended through the first and second respective openings 422 and 424through the tab 492 have curved free ends and fixed ends that areattached to the interior surface of the tab 494. Thus, as force isapplied in the direction of the arrows F to squeeze the tabs 492 and 494toward one another shown in FIG. 26, the proximal and distal force hooks482 and 484 are separated apart from the proximal and distal receptaclecontacts 472 and 474, respectively. This depicted open position of thelock mechanism widens the lateral receptacle slot 480. In the openposition, the lead connector end assembly 12 and the stylet wire 32 canbe laterally inserted or withdrawn through the receptacle slot 480.After the force F is released, the opening of receptacle slot 480decreases to the closed position of FIG. 25 or the locked position witha lead connector end assembly 12 locked in the elongated receptacle 470.

In each of the above-described embodiments, an external lead body 50,150, 250, 350, 450 is disclosed enclosing the two external conductorsthat extend between the receptacle contacts in the respective adaptorconnector assembly to an external lead connector element 48. It will beunderstood that the external lead connector element may take any formthat is compatible with the terminals of the external medical device. Itis also contemplated that the external lead body and external leadconnector element may be replaced by simple external connector assemblyformed integrally with the external lead connector assembly 60, 160,260, 360, 460 to be attached directly to the external medical deviceterminals. In this case, the external conductors would each extend ashort distance between the receptacle contact and the external connectorelement.

The preceding specific embodiments are illustrative of the practice ofthe invention. It is understood therefore that other expedients andequivalents of disclosed components or functions known to those of skillin the art or otherwise disclosed herein may be employed in practicingthe invention without departing from the invention or the scope of thefollowing claims. In this regard, the particular shape of the leadconnector end assemblies and the lead connector elements incorporatedtherein may take any form or arrangement that may be matched in acomplementary fashion by the components forming the elongated receivers.Similarly, the form, number and spacing of the contact terminals formaking contact with the lead connector elements may be modified to becompatible therewith and serve the purposes described above.

The illustrated preferred embodiments are described in the context of abipolar cardiac lead that may be implanted in or applied on the body ofa patient having an in-line connector end assembly. It will beunderstood that the present invention may be implemented in unipolarmedical lead adaptors having only a single external lead conductor,receptacle contact and related components for receiving a unipolar leadconnector end assembly. Conversely, it will be understood that thefeatures of the present invention may be replicated in an elongatedreceptacle and receptacle contacts coupled with respective externalconductors for receiving tri-polar or other multi-polar, in-line, leadconnector end assemblies.

Moreover, it is contemplated that the elongated receptacle in eachembodiment may be dimensioned and configured to receive bipolar andunipolar cardiac lead connector end assemblies that conform with theIS-1 standard or conform to the above-referenced "3.2 mm" connector endassembly, for example. One of the dimensional differences between thesetwo bipolar lead connector end assemblies is the separation between theconnector pin and ring. The preferred embodiments described above may bemodified by providing a common proximal receptacle contact forcontacting the connector pin of each type of lead connector end assemblyand two distal receptacle contacts each spaced from the pin receptaclecontact. The spacing and shape of each distal receptacle contactconforms to the IS-1 and 3.2 mm spacing and ring outer diameter. Both ofthe distal electrical contacts are electrically connected in common withan external conductor. In this manner either type of lead connector endassembly may be accommodated in the same adaptor connector assembly 60,160, 260, 360, 460. By logical extension, the same configuration of anadaptor connector assembly may be effected to accommodate differing leadconnector end assemblies.

In addition, the present invention may be employed in medical leadadaptors for making connections between other implantable or externalmedical leads and external medical equipment. For example, a medicallead adaptor may be configured following the above-described principlesof the present invention to make electrical connections betweenimplantable nerve, muscle or brain stimulation electrode bearing leadsand external stimulators or test equipment.

The various embodiments of the present invention and the variations andequivalents described herein may also be incorporated into a singlemedical lead adaptor for having multiple adaptor connector assembliesattached in combination with an external lead body and external leadconnector assembly. For example, it is envisaged that a single medicallead adaptor for use with a dual chamber pacing lead system may employtwo such adaptor connector assemblies for making connection with atrialand ventricular lead connector end assemblies. The first and secondreceptacle contacts of each adaptor connector assembly are coupled withseparate external conductors and to separate terminals of the externalconnector assembly. The external connector assembly may take any of theknown forms for making electrical connection with the atrial andventricular terminals of the external medical device.

The present invention further includes within its scope methods of usingthe medical lead adaptors of the present invention.

In the following claims, means-plus-function clauses are intended tocover the structures described herein as performing the recited functionand not only structural equivalents but also equivalent structures. Forexample, although a nail and a screw may not be structural equivalentsin that a nail employs a cylindrical surface to secure wooden partstogether, whereas a screw employs a helical surface, in the environmentof fastening wooden parts, a nail and a screw are equivalent structures.

We claim:
 1. An external medical lead adaptor for establishing a rapidelectrical connection between an external medical device connectorassembly and a proximal lead connector end assembly of an implantablecardiac lead of the type having an elongated implantable lead bodyextending from the lead connector end assembly toward a distal cardiaclead end, the implantable lead body containing first and second spacedapart bipolar in-line implantable lead conductors coupled to first andsecond spaced apart proximal lead connector elements of the leadconnector end assembly and having a lumen disposed therein for receivinga stylet wire through a lumen end opening, said stylet wire, whenreceived in said lumen, extending proximally from said lumen end openingof said lead connector end assembly such that said stylet wire may bemanipulated, said medical lead adaptor comprising:external conductormeans comprising at least first and second external electricalconductors, each conductor means extending between a first externalconductor end thereof to a second external conductor end that includesan external connector element for establishing electrical contact withsaid external medical device connector assembly; and an adaptorconnector assembly coupled to said external conductor means forreceiving said lead connector end assembly and for making electricalcontact between said first and second implantable lead conductors andsaid first and second external electrical conductors, respectively, saidadaptor connector assembly further comprising:means for receivingdefining an elongated receptacle having distal and proximal ends forconformably receiving said first and second lead connector elements ofsaid lead connector end assembly when inserted therein; first and secondreceptacle in-line contacts positioned along said elongated receptaclefor establishing electrical contact with said first and second leadconnector elements, respectively; means for electrically connecting eachof said first and second receptacle contacts with said first externalconductor end of said first and second external conductors,respectively; proximal end opening means for receiving and allowing saidstylet wire, to extend proximally from said lead lumen end opening andproximally from the receiving means, said proximal end opening meansdisposed at said proximal end of said receiver means; receptacle slotmeans formed laterally of said elongated receptacle for laterallypassing said lead connector end assembly having said stylet wireextending proximally from said lumen end opening into and out of saidelongated receptacle and said proximal end opening means; and ascrewless and boltless rotatable locking clip mechanism hand manipulableto an open position with respect to said receptacle slot means, saidlocking clip mechanism permitting said implantable lead connector endassembly and stylet wire extending proximally from said lumen endopening to be inserted laterally through said receptacle slot means intosaid receiver means and to be withdrawn laterally from said receivermeans through said receptacle slot means and hand manipulable to alocked position for locking said implantable lead connector end assemblyin said receiver means to assure secure electrical contact between eachreceptacle contact and a corresponding lead connector element whilepermitting manipulation of said stylet wire with respect to said lumen.2. The external medical lead adaptor of claim 1, wherein:said adaptorconnector assembly further comprises a tubular housing enclosing saidelongated receptacle and said first and second receptacle contacts andhaving a cylindrical outer surface extending between proximal and distalhousing ends thereof and having an outer surface circumferential trackdisposed on said generally cylindrical outer surface; said receptacleslot means extends longitudinally along said tubular housing andlaterally between said cylindrical outer surface and said elongatedreceptacle; and said locking clip mechanism is cylindrical and has aninternal tracking surface that engages said outer surfacecircumferential track and is rotatable about said outer surfacecircumferential track between said locked and open positions.
 3. Theexternal medical lead adaptor of claim 2, wherein said locking clipmechanism is generally tubular and has a C-shaped profile defined by anelongated access slot disposed along said length thereof that isalignable with said receptacle slot means on rotation of said lockingclip mechanism to said open position for permitting said implantablelead connector end and stylet wire extending proximally therefrom to beinserted laterally through said aligned access slot and receptacle slotmeans into said elongated receptacle and to be withdrawn laterally fromsaid elongated receptacle through said aligned access slot andreceptacle slot means.
 4. The external medical lead adaptor of claim 3,wherein:said outer surface circumferential track is disposed betweenfirst and second spaced apart rails extending around said circumferenceof said housing, said rails having diameters exceeding said diameter ofsaid circumferential track; and said locking clip mechanism has an innerdiameter that is sized with respect to said rail diameters and saidouter surface track diameter to be restrained by said spaced apart railsand to permit relative rotation of said locking clip mechanism aboutsaid outer surface circumferential track.
 5. The external medical leadadaptor of claim 1, wherein said adaptor connector assembly furthercomprises:a tubular housing of flexible insulating material enclosingsaid elongated receptacle and said first and second receptacle contactsand having a cylindrical outer surface extending between the proximaland distal end openings thereof; said first and second receptaclecontacts comprise thin conductor spring material, the contacts beingspaced apart within said elongated receptacle and dimensioned to tightlyengage said first and second lead connector elements when positioned insaid elongated receptacle in said locked position; and said receptacleslot means comprises a receptacle slot extending longitudinally along aside of said tubular housing and laterally between said cylindricalouter surface and said elongated receptacle having a slot width thatdoes not permit the lead connector end assembly to be passedtherethrough in the closed and locked positions, said tubular housingand said first and second receptacle contacts having a C-shaped profile;and said locking clip mechanism comprises means for increasing the slotwidth from the closed and locked position slot width to an open positionslot width sufficient to permit said elongated lead connector endassembly to pass through said receptacle slot.
 6. An external medicallead adaptor for establishing a rapid electrical connection between anexternal medical device connector assembly and a proximal lead connectorend assembly of an implantable cardiac lead of the type having anelongated implantable lead body extending from the lead connector endassembly toward a distal cardiac lead end, the implantable lead bodycontaining first and second implantable lead conductors coupled tobipolar in-line proximal lead connector elements of the lead connectorend assembly and having a lumen disposed therein for receiving a styletwire through a lumen end opening, the stylet wire, when received in thelumen, extending proximally from the lumen end opening of the leadconnector end assembly such that the stylet wire may be manipulated,said medical lead adaptor comprising:an external lead body comprisingfirst and second external electrical conductors extending between afirst external lead conductor end and a second external lead conductorend that includes an external lead connector element for establishingelectrical contact with the external medical device connector assembly;and an adaptor connector assembly coupled to said external lead body forreceiving the lead connector end assembly and for establishingelectrical contact between each respective implantable lead conductorand each external electrical conductor, said adaptor connector assemblyfurther comprising:means for receiving said adaptor connector assemblydefining an elongated receptacle having distal and proximal ends forconformably receiving each lead connector element of the lead connectorend assembly when inserted therein; first and second in-line receptaclecontacts positioned along said elongated receptacle for establishingelectrical contact with the first and second lead connector elements;means for electrically connecting said receptacle contacts with saidfirst external lead conductor end; proximal end opening means forreceiving and allowing said stylet wire to extend proximally from saidlead lumen end opening and proximally from the receiving means, saidproximal end opening means disposed at said proximal end of saidreceiver means; and receptacle slot means extending laterally of saidelongated receptacle through said adaptor connector assembly to anexterior surface thereof for laterally receiving the lead connector endassembly having the stylet wire extending proximally from said lumen endopening through said receptacle slot means assembly and with each leadconnector element in contact with a receptacle contact; and a screwlessand boltless rotatable locking clip mechanism hand manipulable to anopen position with respect to said receptacle slot means, said lockingclip permitting the implantable lead connector end assembly and styletwire extending proximally from said lumen end opening to be insertedlaterally through said receptacle slot means into said elongatedreceptacle and to be withdrawn laterally from said elongated receptaclethrough said receptacle slot means and hand manipulable to a lockedposition for locking the implantable lead connector end assembly in saidelongated receptacle to assure secure electrical contact between eachreceptacle contact and a corresponding lead connector element whilepermitting manipulation of the stylet wire with respect to said lumen.7. The external medical lead adaptor of claim 6, wherein:said adaptorconnector assembly further comprises a tubular housing enclosing saidelongated receptacle and receptacle contact and having a cylindricalouter surface extending between proximal and distal housing ends thereofand having an outer surface circumferential track disposed on saidcylindrical outer surface; said receptacle slot means extendslongitudinally along said tubular housing and laterally between saidcylindrical outer surface and said elongated receptacle; and saidlocking clip mechanism is cylindrical and has an internal trackingsurface that engages said outer surface circumferential track and isrotatable about said outer surface circumferential track between thelocked and open positions.
 8. The external medical lead adaptor of claim7, wherein said locking clip mechanism is tubular and has a C-shapedprofile defined by an elongated access slot disposed along the lengththereof that is alignable with said receptacle slot means on rotation ofsaid locking clip mechanism to the open position for permitting theimplantable lead connector end and stylet wire extending proximallytherefrom to be inserted laterally through said aligned access slot andreceptacle slot means into said elongated receptacle and to be withdrawnlaterally from said elongated receptacle through the aligned access slotand receptacle slot means.
 9. The external medical lead adaptor of claim7, wherein:said outer surface circumferential track is disposed betweenfirst and second spaced apart rails extending around the circumferenceof said housing, said rails having diameters exceeding the diameter ofsaid circumferential track; and said locking clip mechanism has an innerdiameter that is sized with respect to said rail diameters and saidouter surface diameter to be restrained by said spaced apart rails andto permit relative rotation of said locking clip mechanism about saidouter surface circumferential track.
 10. The external medical leadadaptor of claim 9, wherein said locking clip mechanism is tubular andhas a C-shaped profile defined by an elongated access slot disposedalong the length thereof that is alignable with said receptacle slotmeans on rotation of said locking clip mechanism to the open positionfor permitting the implantable lead connector end and stylet wireextending proximally therefrom to be inserted laterally through thealigned access slot and receptacle slot means into said elongatedreceptacle and to be withdrawn laterally from said elongated receptaclethrough the aligned access slot and receptacle slot means.
 11. Theexternal medical lead adaptor of claim 6, wherein said adaptor connectorassembly further comprises:a tubular housing of flexible insulatingmaterial enclosing said elongated receptacle and said at least onereceptacle contact and having a cylindrical outer surface extendingbetween the proximal and distal end openings thereof; said at least onereceptacle contact comprises a thin conductor spring material, thecontact being disposed within said elongated receptacle and dimensionedto tightly engage the at least one lead connector element whenpositioned in said elongated receptacle in the locked position; and saidreceptacle slot means comprises a receptacle slot extendinglongitudinally along a side of said tubular housing and laterallybetween the cylindrical outer surface and said elongated receptaclehaving a slot width that does not permit the lead connector end assemblyto be passed therethrough in the closed and locked positions, saidtubular housing and said at least one receptacle contact having aC-shaped profile; and said locking clip mechanism comprises means forincreasing the slot width from the closed and locked position slot widthto an open position slot width sufficient to the elongated leadconnector end assembly to pass through said receptacle slot.
 12. Anexternal medical lead adaptor for establishing a rapid electricalconnection between an external medical device connector assembly and aproximal lead connector end assembly of an implantable cardiac lead ofthe type having an elongated implantable lead body extending from thelead connector end assembly toward a distal cardiac lead end, theimplantable lead body containing first and second implantable leadconductors coupled to proximal first and second bipolar in-line leadconnector elements of the lead connector end assembly, said medical leadadaptor comprising:an external lead body comprising external electricalconductors extending between a first external lead conductor end and asecond external lead conductor end that includes first and secondexternal lead connector elements for establishing electrical contactwith the external medical device connector assembly; and an adaptorconnector assembly coupled to said external lead body for receiving thelead connector end assembly and for establishing electrical contactbetween each respective implantable lead conductor and each externalelectrical conductor, said adaptor connector assembly comprising astationary tubular housing and a screwless and boltless rotatablelocking clip mechanism, said tubular housing comprising:means forreceiving internal to said tubular housing defining an elongatedreceptacle having distal and proximal ends for conformably receivingeach lead connector element of the lead connector end assembly wheninserted therein; first and second in-line receptacle contactspositioned along said elongated receptacle for establishing electricalcontact with the first and second lead connector elements; means forelectrically connecting said receptacle contacts with said firstexternal lead conductor end; proximal end opening means for receivingand allowing said stylet wire to extend proximally from said lead lumenend opening and proximally from the receiving means, said proximal endopening means disposed at said proximal end of said receiver means; andreceptacle slot means extending laterally of said elongated receptaclethrough said tubular housing to an exterior surface thereof forlaterally receiving the lead connector end assembly with each leadconnector element in contact with the receptacle contacts; wherein saidlocking clip mechanism is hand manipulable by rotation about saidtubular housing to an open position with respect to said receptacle slotmeans for permitting the implantable lead connector end assembly to beinserted laterally through said receptacle slot means into saidelongated receptacle and to be withdrawn laterally from said elongatedreceptacle through said receptacle slot means and hand manipulable to alocked position for locking the implantable lead connector end assemblyin said elongated receptacle to assure secure electrical contact betweeneach receptacle contact and the corresponding lead connector elements.13. The external medical lead adaptor of claim 12, wherein:said tubularhousing enclosing said elongated receptacle and receptacle contact has acylindrical outer surface extending between proximal and distal housingends thereof and has an outer surface circumferential track disposed onsaid generally cylindrical outer surface; said receptacle slot meansextends longitudinally along said tubular housing between the proximaland distal housing ends and laterally between the cylindrical outersurface and said elongated receptacle; and said locking clip mechanismis cylindrical and has an internal tracking surface that engages saidouter surface circumferential track and is rotatable about said outersurface circumferential track between the locked and open positions. 14.The external medical lead adaptor of claim 13, wherein:said outersurface circumferential track is disposed between first and secondspaced apart rails extending around the circumference of said housing,said rails having diameters exceeding the diameter of saidcircumferential track; and said locking clip mechanism has an innerdiameter that is sized with respect to the rail diameters and the outersurface track diameter to be restrained by said spaced apart rails andto permit relative rotation of said locking clip mechanism about saidouter surface circumferential track.
 15. The external medical leadadaptor of claim 14, wherein said locking clip mechanism is tubular andhas a C-shaped profile defined by an elongated access slot along thelength thereof that is alignable with said receptacle slot disposedmeans on rotation of said locking clip mechanism to the open positionfor permitting the implantable lead connector end to be insertedlaterally through the aligned access slot and receptacle slot means intosaid elongated receptacle and to be withdrawn laterally from saidelongated receptacle through the aligned access slot and receptacle slotmeans.
 16. The external medical lead adaptor of claim 12, wherein saidlocking clip mechanism is tubular and has a C-shaped profile defined byan elongated access slot disposed along the length thereof that isalignable with said receptacle slot means on rotation of said lockingclip mechanism to the open position for permitting the implantable leadconnector end to be inserted laterally through the aligned access slotand receptacle slot means into said elongated receptacle and to bewithdrawn laterally from said elongated receptacle through the alignedaccess slot and receptacle slot means.
 17. The external medical leadadaptor of claim 12, said implantable lead body further having a lumendisposed therein for receiving a stylet wire through a lumen endopening, the stylet wire, when received in the lead lumen, extendingproximally from the lumen end opening of the lead connector end assemblysuch that the stylet wire may be manipulated, wherein:said receptacleslot means extends laterally of said elongated receptacle through saidadaptor connector assembly to an exterior surface thereof, the leadconnector end assembly having the stylet wire extending proximally fromsaid lumen end opening; and said locking clip mechanism is manipulableby rotation about said tubular housing to an open position with respectto said receptacle slot means for permitting the implantable leadconnector end assembly and the stylet wire to be inserted laterallythrough said receptacle slot means in to said elongated receptacle andto be permitting the implantable lead connector end assembly and thestylet wire to be inserted laterally through said receptacle slot meansinto said elongated receptacle and to be withdrawn laterally from saidelongated receptacle through said receptacle slot means and manipulableto a locked position for locking the implantable lead connector endassembly in said elongated receptacle to assure secure electricalcontact between each receptacle contact and a corresponding leadconnector element while permitting manipulation of said stylet wire. 18.The external medical lead adaptor of claim 17, wherein:said tubularhousing enclosing said elongated receptacle and receptacle contact has acylindrical outer surface extending between proximal and distal housingends thereof and an outer surface circumferential track disposed on saidcylindrical outer surface; said receptacle slot means extendslongitudinally along said tubular housing between the proximal anddistal housing ends and laterally between the cylindrical outer surfaceand said elongated receptacle within said tubular housing; and saidlocking clip mechanism cylindrical and has an internal tracking surfacethat engages the outer surface circumferential track and is rotatableabout the outer surface circumferential track between the locked andopen positions.
 19. The external medical lead adaptor of claim 18,wherein:said outer surface circumferential track is disposed betweenfirst and second spaced apart rails extending around the circumferenceof said housing, said rails having diameters exceeding the diameter ofthe circumferential track therebetween; and said locking clip mechanismhas an inner diameter that is sized with respect to the rail diametersand the track surface diameter to be restrained by said spaced apartrails and to permit relative rotation of said lock means about saidouter surface circumferential track.
 20. The external medical leadadaptor of claim 19, wherein said locking clip mechanism is tubular andhas a C-shaped profile defined by an elongated access slot disposedalong the length thereof that is alignable with said receptacle slotmeans on rotation of said locking clip mechanism to the open positionfor permitting the implantable lead connector end with the stiffeningstylet wire extending proximally therefrom to be inserted laterallythrough the aligned access slot and receptacle slot means into saidelongated receptacle and to be withdrawn laterally from said elongatedreceptacle through the aligned access slot and receptacle slot means.21. The external medical lead adaptor of claim 18, wherein said lockingclip mechanism is tubular and has a C-shaped profile defined by amelongated access slot disposed means on rotation of said locking clipmechanism to the open position for allowing the implantable leadconnector end with the stiffening stylet wire extending proximallytherefrom to be inserted laterally through the aligned access slot andreceptacle slot means into said elongated receptacle and to be withdrawnlaterally from said elongated receptacle through the aligned access slotand receptacle slot means.
 22. A method of establishing a rapidelectrical connection between an external medical device connectorassembly and a proximal lead connector end assembly of an implantablecardiac lead of the type having an elongated implantable lead bodyextending from the lead connector end assembly toward a distal cardiaclead end, the implantable lead body comprising first and secondimplantable lead conductors coupled to proximal first and second in-linebipolar lead connector elements of the lead connector end assembly andhaving a lumen disposed therein for receiving a stylet wire through alumen end opening, the stylet wire, when received in the lumen,extending proximally from the lumen end opening of the lead connectorend assembly such that the stylet wire may be manipulated, the methodcomprising the steps of:attaching the external medical device connectorassembly to an external lead connector element of an external lead bodyhaving first and second external electrical conductors disposed thereinand extending between a first external lead conductor end and a secondexternal lead conductor attached to the external lead connector element;and operating an adaptor connector assembly coupled to said externallead body to receive the lead connector end assembly in an elongatedreceptacle thereof to establish electrical contact between therespective first and second implantable lead connector elements andrespective first and second receptacle contacts disposed within theelongated receptacle and electrically coupled to their respectiveexternal electrical conductors, the operating step further comprisingthe steps of:opening, by rotating a screwless and boltless locking clipmechanism to an exterior surface of the adaptor connector assembly, areceptacle slot extending laterally of said elongated receptacle withinsaid adaptor connector assembly to an exterior surface thereof tolaterally receive the lead connector end assembly having the stylet wireextending proximally from the lumen end opening through said receptacleslot; laterally inserting the lead connector end assembly having thestylet wire extending proximally from said lumen end opening throughsaid receptacle slot and into an elongated receptacle shaped toconformably receive the first and second lead connector elements of thelead connector end assembly when inserted therein, the elongatedreceptacle having first and second in-line receptacle contactspositioned along said elongated receptacle for establishing electricalcontact with the lead connector elements, said first and secondreceptacle contacts being electrically connected to said first externallead conductor end; closing the receptacle slot, by rotating the lockingclip mechanism, to lock the implantable lead connector end assembly insaid elongated receptacle to assure secure electrical contact betweenthe first and second receptacle contacts and the first and second leadconnector elements; and permitting manipulation of the stylet wire withrespect to said lumen through a proximal end opening means for receivingand allowing said stylet wire to extend proximally from said lead lumenend opening and proximally from the adaptor connector assembly, saidproximal end opening means disposed at a proximal end of said adaptorconnector assembly.
 23. The method of claim 22, wherein said closingstep further comprises:rotating a cylindrical clip on a clip internaltracking surface about a cylindrical outer surface of a tubular housingenclosing said elongated receptacle and receptacle contact and havingsaid receptacle slot disposed therein to extend longitudinally alongsaid tubular housing and laterally between said generally cylindricalouter surface and said elongated receptacle such that the clip bodyoverlies said receptacle slot.
 24. The method of claim 23, wherein:saidelongated receptacle is configured to receive a multi-polar, in-line,lead connector end assembly having a proximal connector pin and at leastone additional distal connector ring coupled with at least first andsecond implantable lead conductors mutually insulated from one anotherand spaced apart along the length of the lead connector end assembly; atleast two receptacle contacts are positioned along said elongatedreceptacle for making electrical contact with the lead connector pin andring; and at least two external lead conductors within said externallead body are electrically connected to said at least two receptaclecontacts.
 25. The method of claim 23, wherein said opening step furthercomprises:rotating said cylindrical clip on said clip internal trackingsurface about said cylindrical outer surface of said tubular housing toan open position positioning an elongated access slot extending alongthe length thereof in alignment with said receptacle slot to permit theimplantable lead connector end and stylet wire extending proximallytherefrom to be inserted laterally through said aligned access slot andreceptacle slot into said elongated receptacle and to be withdrawnlaterally from said elongated receptacle through the aligned access slotand receptacle slot.
 26. The method of claim 25, wherein:said elongatedreceptacle is configured to receive a multi-polar, in-line, leadconnector end assembly having a proximal connector pin and at least oneadditional distal connector ring coupled with at least first and secondimplantable lead conductors mutually insulated from one another andspaced apart along the length of the lead connector end assembly; atleast two receptacle contacts are positioned along said elongatedreceptacle for establishing electrical contact with the lead connectorpin and ring; and at least two external lead conductors within saidexternal lead body are electrically connected to said at least tworeceptacle contacts.
 27. The method of claim 22, wherein:said elongatedreceptacle is configured to receive a multi-polar, in-line, leadconnector end assembly having a proximal connector pin and at least oneadditional distal connector ring coupled with at least first and secondimplantable lead conductors mutually insulated from one another andspaced apart along the length of the lead connector end assembly; atleast two receptacle contacts are positioned along said elongatedreceptacle for establishing electrical contact with the lead connectorpin and ring; and at least two external lead conductors within saidexternal lead body are electrically connected to said at least tworeceptacle contacts.
 28. The method of claim 27, wherein said openingstep further comprises increasing the receptacle slot width of saidreceptacle slot from a closed slot width that precludes lateralinsertion of the lead connector end assembly having the stylet wireextending proximally from said lumen end opening through said receptacleslot.
 29. An apparatus for establishing a rapid electrical connectionbetween an external medical device connector assembly and a proximallead connector end assembly of an implantable cardiac lead of the typehaving an elongated implantable lead body extending from the leadconnector end assembly toward a distal cardiac lead end, the implantablelead body comprising first and second implantable lead conductorscoupled to proximal bipolar in-line first and second lead connectorelements of the lead connector end assembly and having a lumen disposedtherein for receiving a stylet wire through a lumen end opening, thestylet wire, when received in the lumen, extending proximally from thelumen end opening of the lead connector end assembly such that thestylet wire may be manipulated, the apparatus comprising:means forattaching the external medical device connector assembly to an externallead body having first and second external electrical conductorsdisposed therein and extending between a first external lead conductorend and a second external lead conductor end; an adaptor connectorassembly coupled to the second external lead conductor end at saidexternal lead body to receive the lead connector end assembly, theadaptor connector assembly having an elongated receptacle disposedtherein for establishing electrical contact between the first and secondimplantable lead connector elements and the first and second receptaclecontacts disposed within the elongated receptacle, the adaptor connectorassembly further comprising a receptacle slot extending laterally ofsaid elongated receptacle to an exterior surface of said adaptorconnector assembly and proximal end opening means for receiving andallowing said stylet wire to extend proximally from said lead lumen endopening and proximally from the adaptor connector assembly, saidproximal end opening means disposed at a proximal end of said adaptorconnector assembly; and a screwless and boltless rotatable locking clipmechanism operable between an open position for opening the receptacleslot to laterally receive the lead connector end assembly therein, thelead connector end assembly having the stylet wire extending proximallyfrom said lumen end opening and being disposed in an elongatedreceptacle shaped to conformably receive the first and second leadconnector elements of the lead connector end assembly, and a lockedposition for closing the receptacle slot to lock the implantable leadconnector end assembly in said elongated receptacle to assure secureelectrical contact between the first and second receptacle contacts andthe first and second lead connector elements while permittingmanipulation of the stylet wire with respect to said lumen.
 30. Theapparatus of claim 29, wherein:said elongated receptacle is configuredto receive a lead connector end assembly having a proximal connector pinand at least one additional distal connector ring coupled to at leastfirst and second implantable lead conductors mutually insulated from oneanother and spaced apart along the length of the lead connector endassembly; at least two receptacle contacts are positioned along saidelongated receptacle for establishing electrical contact with the leadconnector pin and ring; and at least two external lead conductorsdisposed within said external lead body being electrically connected tosaid at least two receptacle contacts.
 31. The apparatus of claim 30,wherein said locking clip mechanism further comprises:means movableabout said adaptor connector assembly housing between an open wherein anelongated access slot extends along the length thereof in alignment withsaid receptacle slot to permit the implantable lead connector end andstylet wire extending proximally therefrom to be inserted laterallythrough said aligned access slot and receptacle slot into said elongatedreceptacle and to be withdrawn laterally from said elongated receptaclethrough the aligned access slot and receptacle slot and a lockedposition covering said receptacle slot.
 32. The apparatus of claim 30,wherein said locking clip mechanism further comprises means forincreasing the receptacle slot width of said receptacle slot from aclosed slot width that precludes lateral insertion through saidreceptacle slot of the lead connector end assembly having the styletwire extending proximally from said lumen end opening.